InChI=1S/C16H18O9/c17-10-11(18)13(15(22)23)25-16(12(10)19)24-7-9(14(20)21)6-8-4-2-1-3-5-8/h1-6,10-13,16-19H,7H2,(H,20,21)(H,22,23)/b9-6-